Add vp9 QP parser.

webrtc/modules/video_coding/utility/vp9_uncomp_header_parser.h

+/*
+ *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_MODULES_VIDEO_CODING_UTILITY_VP9_UNCOMP_HEADER_PARSER_H_
+#define WEBRTC_MODULES_VIDEO_CODING_UTILITY_VP9_UNCOMP_HEADER_PARSER_H_
+
+#include <stdint.h>
+#include <stdio.h>

[brandtr, 2017/05/19 14:10:27]

Do you need this?

[jianj1, 2017/05/19 21:20:56]

size_t will need it. I changed it to <stddef.h>

+
+namespace webrtc {
+
+namespace vp9 {
+
+typedef struct VP9BitReader VP9BitReader;

[brandtr, 2017/05/19 14:10:27]

Don't think you would need this in C++.

[jianj1, 2017/05/19 21:20:56]

Done.

+struct VP9BitReader {
+  const uint8_t *buf_;

[brandtr, 2017/05/19 14:10:27]

Although the style guide allows it, we typically put the star next to the type
in WebRTC.

Also, we typically don't use underscores for field names in structs.

[jianj1, 2017/05/19 21:20:57]

Done.

+  const uint8_t *buf_end_;
+  size_t offset_;
+};
+
+// Gets the QP, QP range: [0, 255].
+// Returns true on success, false otherwise.
+bool GetQp(const uint8_t *buf, size_t length, int *qp);

[brandtr, 2017/05/19 14:10:27]

const uint8_t*

[jianj1, 2017/05/19 21:20:56]

Done.

+
+}  // namespace vp9
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_VIDEO_CODING_UTILITY_VP9_UNCOMP_HEADER_PARSER_H_